silver border with gold insignia. At that time, lieutenant colonels and majors were authorized leaves, captains were authorized two bars, and first lieutenants were authorized one bar on the shoulder straps. 1851–1872: epaulettes vs. shoulder straps In 1851, it was decided to use only silver eagles for colonels, as a matter of economy. The silver eagle was selected based on the fact that there were more colonels with the silver eagle that those with gold, primarily in the cavalry and artillery, hence it was cheaper to replace the numerically fewer gold ones in the infantry. At that time on the shoulder straps, lieutenant colonels wore an embroidered silver leaf; majors wore a gold embroidered leaf; and captains and first lieutenants wore gold bars. The second lieutenant had no grade insignia, but the presence of an epaulet or shoulder strap identified him as a commissioned officer. For majors, the shoulder strap contained an oak leaf, but like the second lieutenant, the epaulet had no grade insignia. However, the major was still distinguishable from the second lieutenant due to the more elaborate epaulet fringes worn by field grade officers. Prior to 1851 the infantry wore shoulder straps that had a silver border with gold insignia, the other branches wore gold border with silver insignia. The rank of major and lieutenant colonel were designated by oak leaves. A lieutenant colonel was determined by the color of the border, so an infantry Lt. Col. wore silver oak leaves, and other branches wore gold oak leaves. In 1851 the Army did away with the infantry distinctions, with everyone going to gold borders. Senior officers, lieutenant colonels, colonels, and generals wore silver insignia. Second lieutenants had no rank, first lieutenants, captains, and majors wore gold insignia. In 1872 the ranks of first lieutenant and captain reverted to silver insignia. 1872–1917: shoulder straps In 1872, epaulettes were abolished for officers and replaced by shoulder knots. As the shoulder knots had no fringe, it was necessary that some change in the insignia on the dress uniform be made in order to distinguish the major from the second lieutenant. It was natural to use the gold leaf which the major had been wearing on the shoulder strap. In the same year, the bars on the shoulder straps of the captains and first lieutenants were changed from gold to silver. 1917–2014: shoulder loops By 1917 and the time of World